Hospital bed

ABSTRACT

A hospital bed having an adjustable head section which is preferably combined with an adjustable seat section. A head gatch mechanism couples the head section to the bed frame and can be operated to move the head and seat sections from a horizontal position into a position in which the seat section is inclined downwardly towards the head section which is inclined upwardly. The mechanism is adjustable for patient weight so that the head section can be made to follow patient movement between supine and sitting positions.

United States Patent 1 1 1111 3,877,088

Bouman Apr. 15, 1975 [54] HOSPITAL BED 3,230,554 1/1966 Peterson ..5/66

[75] Inventor: Wim John Michael Bouman,

Tcronto, Ontario, Canada Primary Examzner-Paul R. Gllllam AssistantExaminer- Kenneth J. Dorner [73] Assignee: Metal Craft (1970) Limited,Attorney, Agent, or Firm-Rogers, Bereskin & Parr Beamsville, Ontario,Canada 221 Filed; June 18, 1973 [57] ABSTRACT A hospital bed having anadjustable head section [21] Appl' 370,774 which is preferably combinedwith an adjustable seat section. A head gatch mechanism couples the head[52] US. Cl. 5/66 Section to the bed frame and can be Operated to move51 1111. C1 A61g 7/06 the head and Seat Sections from a horizontalPosition 58 Field 61 Search 5/60, 66, 67, 68, 69 into a position inwhich the seat section is inclined downwardly towards the head sectionwhich is in- 5 References Cited clined upwardly. The mechanism isadjustable for pa- UNITED STATES PATENTS tient weight so that the headsection can be made to 194 263 12/1933 M l t h follow patient movementbetween supine and sitting 3,191,990 6/1965 Rugg Cl 8L... 5 66 postlons'3,212,817 10/ 1965 Sully 297/429 5 Claims, 6 Drawing Figures 54 3s szi h1 70 36 72 92 94 34 2 5s v j 16 /6 56 q 62 76 7m, 24 L ,l-2a 96102 i 6'68 4 68 2e PATENTEBAPR l 5%575 mw 9 wm HOSPITAL BED This inventionrelates to hospital beds, and more particularly to a hospital bed havinga head section which can be moved between lowered and raised positionsby a patient moving himself between respective supine and sittingpositions.

Hospital beds are commonly provided with various adjustments which areconsidered necessary both from a medical standpoint and also from thestandpoint of patient comfort. One of these adjustments commonly permitsa head section to be moved between a horizontal or lowered position andan inclined or raised position. An improvement on this adjustment is toalso provide a seat section which is coupled to the head section andwhich becomes inclined downwardly towards the head section as the headsection is inclined upwardly. Consequently, in a sitting position, theseat section tends to better locate the patient against sliding movementdown the bed and is therefore more comfortable for the patient. I

The head section is commonly elevated by a manual actuator located atthe foot of the bed and operated by a nurse when the patient wishes tochange his position. Consequently. the patient must first call a nursebefore such a bed can be adjusted. An alternative arrangement is toprovide an electrical control which the patient can operate himself.Although such controls are used with success. they nevertheless sufferfrom the disadvantages both that they are relatively expensive and thatthey must include safety controls which are designed to make itdifficult for a patient to injure himself by accidental misuse of theelectrical control.

It is an object of the present invention to provide a head section whichwill move between a lowered or horizontal position and a raised orinclined position as a patient moves himself between the supine andsitting positions.

It is a further object of the invention to provide a combination headsection and seat section which move to support a patient as the patientmoves between a supine position and a sitting position.

Accordingly. in one of its aspects. the present invention provides ahospital bed having an adjustable head section on a bed frame. A headgatch mechanism couples the head section to the bed frame and can beoperated to raise and lower the head section. The mechanism isadjustable for patient weight so that the head section can be made tofollow patient movement between supine and sitting positions.

In another of its aspects the present invention provides a hospital bedhaving adjustable head and seat sections pivotally connected to oneanother and coupled to a bed frame. A head gatch mechanism couples thehead section to the bed frame and can be operated to move the head andseat sections from a horizontal position into a position in which theseat section is inclined downwardly towards the head section which isinclined upwardly. The mechanism is adjustable for patient weight sothat the head section can be made to follow patient movement betweensupine and sitting positions.

These and other aspects of the invention will be better understood withreference to the drawings. in which:

FIG. I is a perspective view of a bed incorporating the invention.

FIG. 2 is a side view of the bed with parts in section to illustratehidden detail and including a double-acting locking mechanism in alocked position;

FIG. 3 is a sectional view on line 3-3 of FIG. 2;

FIG. 4 is a sectional view on line 4-4 of FIG. 2;

FIG. 5 is a sectional side view of the double-acting locking mechanismin a released position; and

FIG. 6 is a view similar to FIG. 2 showing the bed in another position.

Reference is first made to FIG. 1 which shows an exemplary bed frame 10to which is attached a head gatch mechanism 12 for use in adjusting thehead section 14 and seat section 16 of a mattress support 18. Thissupport is adapted to carry a conventional mattress such as thatindicated at 19 in FIG. 2.

The bed frame 10 is typical of any suitable frame and includeslongitudinal members 20, 22 connected at their ends to respectivetransverse members 24, 26. The longitudinal and transverse membersdefine a rectangular frame and four legs 28 extended downwardly fromcorners of this frame. As is conventional, the legs are supported attheir lower ends on respective castors 30.

Three support members 32, 34, and 36 extend transversely between thelongitudinal members 20, 22. Each of the support members is in the formof a shallow inverted U and these members are positioned so that themembers 32, 34 support a leg section 38 of the mattress support 18 andthe member 36 supports an outer end of the head section 14.

The leg section 38 is attached to the members 32, 34 and is connected bya pair of pivots 40 (one of which is shown) to the seat section 16.Pivots 42 at the other end of the seat section 16 connect this sectionto the head section 14. The respective pivots 40, 42 lie on paralleltransverse axes. Head section 14 is also supported by a pair of links44, 46 which are connected at their respective lower inner sides of thelongitudinal members 20, 22 by pivots 48, 50 and to the head section 14by pivots 52, 54. The links 44, 46 combine with the head gatch mechanism12 to control the movement of the seat section 16 and head section 14 asthese sections move between the positions shown in FIGS. 1 and 6. Thesemovements will be described after completing description of thestructural components of the head gatch mechanism 12.

Reference is now made to FIGS. 1 and 2 with particular reference to FIG.2 to described the head gatch mechanism 12. This inechanism is operatedmanually by a crank 56 on an outer end of a shaft 58 which is carried ina swivel bearing 60 on the transverse member 24 of the frame 10. Theshaft 58 is threaded at its inner end for engagement in threaded endpiece 62 of a first element 64. This element is telescoped at itsforward end in a second element 66 for relative axial movement of oneelement relative to the other element. The element 66 is connected by apivot 68 to a distal end of a heavy bracket 70 attached to the undersideof the head section 14 adjacent the pivots 42.

The element 64 includes a cover 72 having a generally U-shaped sectionand attached at its end to the end piece 62. A fillet 74 is alsoattached to the cover 72 and is adapted to slidably receive an elongatedhardened shaft 76 forming part of the second element 66. As seen in FIG.3, this shaft is also located between a pair of transverse pins 78, 80which are engaged in the cover 72. A washer 82 is held against thesepins by a compression spring 84 contained in the second element 66.

The cover 72 also has a pair of pins 86, 88 attached to it above theshaft 76 between the fillet 74 and the pins 78, 80. The pins 86, 88 formparts of a doubleacting locking mechanism 90 which is adapted to limitrelative movement between the elements 64, 66 as will be described. Themechanism 90 includes a pair of similar locking elements 92, 94 whichare biased away from one another by respective tension springs 96, 98anchored in opposition in the cover 72. These elements are of a materialwhich complements the shaft 76 to permit the elements to lock the shaftfrictionally without substantial damage either to the elements or to theshaft. Locking element 94 is typical of both locking elements and isbetter seen in FIG. 4. The element 94 fits relatively snugly inside thecover 72 to locate the element 94 transversely and the shaft 76 passesthrough the element 94 loosely. The spring 98 biases the element intofrictional engagement with the shaft 76 and this frictional engagementwill become sufficient to lock the element to the shaft under certainconditions which will be described.

Returning to FIG. 2, the frictional engagement of the locking elements92, 94 on the shaft 76 can be relieved by actuating a hand control 100which is connected by a sheathed cable 102 to the locking mechanism 90.On operating the hand control the sheath bears against the lockingelement 92 and the cable pulls the locking ele ment 94 so that theelements are moved toward one another into a position such as that shownin FIG. 5. In this position there is a minimal frictional engagementbetween the locking elements 92, 94 and the shaft 76 so that theelements 64, 66 are no longer locked to one another.

The element 66 includes a cover 104 to which an anchor 106 is attachedfor connecting an end of the shaft 76 to the cover 104. The compressionspring 84 is retained in compression between the washer 82 (FIG. 3) andthe anchor 106 to bias the elements 64, 66 apart when the lockingmechanism 90 is in the position shown in FIG. 5. The significance ofthis arrangement will become apparent upon describing the operation ofthe bed as follows.

In use, the head gatch mechanism 12 can be used conventionally with thehandle control 100 in the normal or locked position corresponding to theposition of the locking mechanism 90 shown in FIG. 2. In effect theelements 64 and 66 are then locked to one another and form theequivalent of a single link connecting the heavy bracket 70 on theunderside of the head section 14 to the threaded shaft 58 which isattached to the crank 56. Consequently, upon rotating the crank in adirection corresponding to raising the head section, the bracket 70 ismade to rotate in a generally anticlockwise direction as drawn in FIG.2. Consequently, the head section 14 also rotates guided by itsconnection with the seat section 16 and the respective links 44, 46(FIG. 1). Further rotation of the crank 56 will ultimately result in thesections 14 and 16 taking the positions shown in FIG. 6 in which thehead section 14 is at an angle of about 60 degrees to the horizontal.The seat section 16 is then inclined downwardly from the leg section 38to better locate the patient in a sitting position.

Returning to FIG. 2, it will be evident that use of the head gatchmechanism as just described requires that a nurse is available. However,the combination of the first and second elements 64, 66 is also intendedto permit the patient to raise and lower himself as will now bedescribed.

Imagine the situation in which the compression spring 84 is compressedsufficiently that it tends to force the second element 66 away from thefirst element 64 to raise the head section 14. Such a substantial forcefrom the spring 84 causes the friction in the locking element 94 of thelocking mechanism to tend to move towards the associated spring 98 aboutthe pin 88. This attempted movement will result in increased reactionforces between the locking element 94 and the shaft 76 to lock the shaft76 in position relative to the element 74. Consequently, no movement cantake place in this condition. Also, if a patient or nurse were toattempt to unlock the mechanism 90 by operating the hand control 100,the result would simply be that the locked element 94 would be unmovedand the other element 92 would be free to move under the influence ofthe sheathed cable 102. The mechanism would however, remain locked. Itwill therefore be evident that the mechanism 90 can be unlocked bypressing downwardly on the head rest to balance the force exerted by thespring 84 on the mechanism 90. The crank 56 can then be rotated to relaxthe spring until the upward force at the head rest is removed.

Consider now the situation shown in FIG. 2 in which the spring 84 isrelaxed and a patient is lying on the bed. The mechanism 12 is adjustedby operating the hand control and turning the crank 56 until the headsection is about to move upwardly. The patient then balances the springforce and if the patient moves towards a sitting position the seatsection 16 and head section 14 will follow him as seen in FIG. 6. If hegets out of bed, then the locking element 94 will come into playautomatically to prevent sudden movement of the head and seat sectionsunder the influence of the compressed spring 84. When a patient is togive up his bed to another patient it is preferable to relax the spring84 by turning the crank 56. The mechanism is then adjusted to the weightof the next patient by turning crank 56 to compress the spring aspreviously described with reference to the first patient. However, ifthe first patient simply leaves the bed set for him and a lighter orheavier second patient then takes the bed, it will be necessary toreadjust the bed.

In the case of a lighter second patient his weight will not besufficient to unlock the locking element 94. Consequently, he can do oneof two things. Firstly he can apply more weight to the head section bymoving himself or by having a nurse help him by pushing down on thissection. This permits the hand control to release the locking element 94and the crank 56 is then used to relax the spring to a condition inwhich the second patient is balanced. Secondly he can have a nurse turnthe crank 56 to raise the head section until the limit of the travel isreached to balance the spring force. Consequently the locking elements92, 94 can then be released using the control 100 and the crank is thenused to allow the spring to relax to the desired condition to balancethe patient.

In the case ofa heavier second patient his weight will tend to cause thelocking element 92 to lock to the shaft 76. Here again there are twopossibilities. Firstly, the patient can reduce the weight on the headsection either by raising himself slightly or by having a nurse apply anupward force to the head section to permit the control 100 to berelaxed. The crank 56 is then turned to re-set the spring compression tomatch the second patients weight. Secondly, he can have a nurse turn thecrank 56 to lower the head section to the limit of its travel which willcause a reaction between the head section and the support member 36sufficient to permit the control 100 to release the locking element 92,94 so that the spring 84 can be adjusted.

It will now be evident that when the mechanism 12 is adjusted, the headsection 14 and seat section 16 move towards a sitting position under theinfluence of the spring 84 and return to the lowered or flat positionunder the influence of the patient's weight. Also, it is necessary tore-set the mechanism 12 whenever a new patient uses the bed unless thispatient happens to have substantially the same weight characteristics asthe previous patient.

Although the preferred embodiment shown in the drawings includes apivotal seat section, the principle ofa balanced head section can alsobe applied to a mattress frame in which the seat section 16 ispermanently aligned with the leg section 38. In such a structure thelinks 44, 46 could be eliminated and the head section would be supportedat pivots 42 during movement above the support member 36. While astructure of this type is within the scope of the invention theembodiment described with reference to the drawings provides greateradvantages and is therefore considered to be preferable.

In some instances electric actuation could be preferable. The crank 56would then be removed in favour of an electric motor and gear box todrive the shaft 58. Generally the crank 56 and shaft 58 are typical ofany suitable actuator means adapted to cause the head and seat sectionsto move as described.

I claim:

1. A hospital bed comprising:

a bed frame;

a mattress support coupled to the bed frame and including a head sectionrotatable about a horizontal axis between a horizontal position and araised position in which the head section is inclined upwardly from saidaxis;

a head gatch mechanism comprising: first and second elements coupledtogether for axial telescopic movement relative to one another; abracket attached to the head section and pivotally connected at a distalend thereof to an end of the second element remote from the firstelement; spring means coupled at its ends to said first and secondelement and adapted to bias the first element axially away from thesecond element; a double-acting locking mechanism coupled to the firstand second elements and adapted to prevent relative movement between thefirst and second elements when a substantial force is applied to moveone of said elements axially with respect to the other of the elements;control means coupled to the locking mechanism and operable to unlockthe mechanism when said substantial force is removed; and actuactormeans coupling the first element to the bed frame and adapted to movethe first element axially relative to the bed frame, whereby when thebed is in use. the head gatch mechanism can be adjusted to the weightofa patient on the bed by first operating the control means to releasethe locking mechanism to permit relative movement between the first andsecond elements, and then moving the said first element axially usingthe actuactor means, so as to vary the biassing effect to the springmeans until the said effect is balanced by the weight of the patient.

2. A hospital bed as claimed in claim 1 in which the second elementincludes a shaft and the first element includes means locating the shaftfor longitudinal movement as the elements telescope relative to oneanother, and in which the locking mechanism comprises a pair of lockingelements engaged about the shaft and movable between a released positionin which the locking elements are generally perpendicular to the shaftand a locked position in which the locking elements are inclined withrespect to the shaft for frictionally engaging the shaft; location meanscoupled to the first element and adapted to locate the locking elementsrelative to the first element such that the locking elements can pivotabout said location means between said released and locked positions;and means biassing the locking elements towards said locked positions;the said control means being adapted to permit the locking elements tobe moved from the locking positions into the released positions uponremoval of said substantial force.

3. A hospital bed comprising:

a bed frame; I

a mattress support coupled to the bed frame and including a headsection, a seat section, and a leg section the seat section beingpivotally coupled to the leg section for movement about an axis betweena horizontal position and an inclined position in which the seat sectionslopes downwardly from the leg section, and the head section beingpivotally connected to the seat section for movement about another axisparallel to said first mentioned axis between a lowered position inplanar alignment with the seat section when the seat section is in thehorizontal position and a raised position in which the head section isinclined upwardly from said another axis with the seat section being inthe inclined position;

link means coupling the head section to the bed frame to at least partlysupport the head section as this section moves between the lowered andraised positions;

a head gatch mechanism comprising: first and second elements coupledtogether for axial telescopic movement relative to one another; abracket attached to the head section and pivotally connected at a distalend thereof to an end of the second element remote from the firstelements; spring means coupled at its ends to said first and secondelements and adapted to biass the first element axially away from thesecond element; a double-acting locking mechanism coupled to the firstand second elements and adapted to prevent relative movement between thefirst and second elements when a substantial force is applied to moveone of said elements axially with respect to the other of the elements;control means coupled to the locking mechanism and operable to unlockthe mechanism when said substantial force is removed; and actuactormeans coupling the first element to the bed frame and adapted to movethe first element axially relative to the bed frame, whereby when thebed is in use, the head gatch mechanism can be adjusted to the weight ofa patient on the bed by first operating the control means to release thelocking mechanism to permit relative movement between the first andsecond elements, and then moving the said first element axially usingthe actuactor means, so as to vary the biassing effect of the springmeans until the said effect is balanced by the weight of the patient. 4.In a hospital bed of the type having a bed frame, a mattress supportedabove the frame and coupled to the bed frame, and a head gatch mechanismcoupled to the bed frame and to a head section of the mattress supportfor moving the head section between a horizontal position and aninclined position, the improvement in which the head gatch mechanismcomprises: first and second elements telescopically interconnected foraxial movement relative to one another; spring means coupled at its endsto said first and second elements, said spring means. biasing theelements away from one another; means coupling the second element to thehead section; a double acting locking mechanism coupled to the first andsecond elements and adapted to prevent movement between the first andsecond elements when a substantial force is applied to move one of saidelements; and actuactor means coupled to the first element and to thebed frame and adapted to move the first element axially relative to thebed frame, whereby when the bed is in use, the head gatch mechanism canbe adjusted to the weight of a patient on the bed by first releasing thelocking mechanism to permit relative movement between the first andsecond elements, and then by moving the said first element axially usingthe actuactor means so as to vary the biassing effect of the springmeans until the said effect is balanced by the weight of the patient.

5. Apparatus as claimed in claim 4 in which the second element includesa shaft and the first element includes means locating the shaft forlongitudinal movement as the elements telescope relative to one another,and in which the locking mechanism comprises a pair of locking elementsengaged about the shaft and movable between a released position in whichthe locking elements are generally perpendicular to the shaft and alocked position in which the locking elements are inclined with respectto the shaft for frictionally engaging the shaft; location means coupledto the first element and adapted to locate the locking elements relativeto the first element such that the locking elements can pivot about saidlocation means between said released and locked positions; meansbiassing the locking elements towards said locked positions; and controlmeans adapted permit the locking elements to be moved from the lockingpositions into the released positions upon removal of said substantialforces.

1. A hospital bed comprising: a bed frame; a mattress support coupled tothe bed frame and including a head section rotatable about a horizontalaxis between a horizontal position and a raised position in which thehead section is inclined upwardly from said axis; a head gatch mechanismcomprising: first and second elements coupled together for axialtelescopic movement relative to one another; a bracket attached to thehead section and pivotally connected at a distal end thereof to an endof the second element remote from the first element; spring meanscoupled at its ends to said first and second element and adapted to biasthe first element axially away from the second element; a double-actinglocking mechanism coupled to the first and second elements and adaptedto prevent relative movement between the first and second elements whena substantial force is applied to move one of said elements axially withrespect to the other of the elements; control means coupled to thelocking mechanism and operable to unlock the mechanism when saidsubstantial force is removed; and actuactor means coupling the firstelement to the bed frame and adapted to move the first element axiallyrelative to the bed frame, whereby when the bed is in use, the headgatch mechanism can be adjusted to the weight of a patient on the bed byfirst operating the control means to release the locking mechanism topermit relative movement between the first and second elements, and thenmoving the said first element axially using the actuactor means, so asto vary the biassing effect to the spring means until the said effect isbalanced by the weight of the patient.
 2. A hospital bed as claimed inclaim 1 in which the second element includes a shaft and the firstelement includes means locating the shaft for longitudinal movement asthe elements telescope relative to one another, and in which the lockingmechanism comprises a pair of locking elements engaged about the shaftand movable between a released position in which the locking elementsare generally perpendicular to the shaft and a locked position in whichthe locking elements are inclined with respect to the shaft forfrictionally engaging the shaft; location means coupled to the firstelement and adapted to locate the locking elements relative to the firstelement such that the locking elements can pivot about said locationmeans between said released and locked positions; and means biassing thelocking elements towards said locked positions; the said control meansbeing adapted to permit the locking elements to be moved from thelocking positions into the released positions upon removal of saidsubstantial force.
 3. A hospital bed comprising: a bed frame; a mattresssupport coupled to the bed frame and including a head section, a seatsection, and a leg section, the seat section being pivotally coupled tothe leg section for movement about an axis between a horizontal positionand an inclined position in which the seat section slopes downwardlyfrom the leg section, and the head section being pivotally connected tothe seat section for movement about another axis parallel to said firstmentioned axis between a lowered position in planar alignment with theseat section when the seat section is in the horizontal position and araised position in which the head section is inclined upwardly from saidanother axis with the seat section being in the inclined position; linkmeans coupling the head section to the bed frame to at least partlysupport the head section as this section moves between the lowered andraised positions; a head gatch mechanism comprising: first and secondelements coupled together for axial telescopic movement relative to oneanother; a bracket attached to the head section and pivotally connectedat a distal end thereof to an end of the second element remote from thefirst elements; spring means coupled at its ends to said first andsecond elements and adapted to biass the first element axially away fromthe second element; a double-acting locking mechanism coupled to thefirst and second elements and adapted to prevent relative movementbetween the first and second elements when a substantial force isapplied to move one of said elements axially with respect to the otherof the elements; control means coupled to the locking mechanism andoperable to unlock the mechanism when said substantial force is removed;and actuactor means coupling the first element to the bed frame andadapted to move the first element axially relative to the bed frame,whereby when the bed is in use, the head gatch mechanism can be adjustedto the weight of a patient on the bed by first operating the controlmeans to release the locking mechanism to permit relative movementbetween the first and second elements, and then moving the said firstelement axially using the actuactor means, so as to vary the biassingeffect of the spring means until the said effect is balanced by theweight of the patient.
 4. In a hospital bed of the type having a bedframe, a mattress supported above the frame and coupled to the bedframe, and a head gatch mechanism coupled to the bed frame and to a headsection of the mattress support for moving the head section between ahorizontal position and an inclined position, the improvement in whichthe head gatch mechanism comprises: first and second elementstelescopically interconnected for axial movement relative to oneanother; spring means coupled at its ends to said first and secondelements, said spring means. biasing the elements away from one another;means coupling the second element to the head section; a double actinglocking mechanism coupled to the first and second elements and adaptedto prevent movement between the first and second elements when asubstantial force is applied to move one of said elements; and actuactormeans coupled to the first element and to the bed frame and adapted tomove the first element axially relative to the bed frame, whereby whenthe bed is in use, the head gatch mechanism can be adjusted to theweight of a patient on the bed by first releasing the locking mechanismto permit relative movement between the first and second elements, andthen by moving the said first element axially using the actuactor meansso as to vary the biassing effect of the spring means until the saideffect is balanced by the weight of the patient.
 5. Apparatus as claimedin claim 4 in which the second element includes a shaft and the firstelement includes means locating the shaft for longitudinal movement asthe elements telescope relative to one another, and in which the lockingmechanism comprises a pair of locking elements engaged about the shaftand movable between a released position in which the locking elementsare generally perpendicular to the shaft and a locked position in whichthe locking elements are inclined with respect to the shaft forfrictionally engaging the shaft; location means coupled to the firstelement and adapted to locate the locking elements relative to the firstelement such that the locking elements can pivot about said locationmeans between said released and locked positions; means biassing thelocking elements towards said locked positions; and control meansadapted permit the locking elements to be moved from the lockingpositions into the released positions upon removal of said substantialforces.